Prehospital Blood Transfusion in New South Wales, Australia: A Retrospective Cohort Study.

INTRODUCTION: Catastrophic hemorrhage remains the leading cause of preventable death. Not all New South Wales (NSW) hospitals stock blood products and, as such, blood products carried by NSW Ambulance retrieval teams are often the first available to critically unwell patients. OBJECTIVE: To describe the trends, characteristics and predictors of mortality prior to hospital treatment in patients receiving prehospital blood transfusion by NSW Ambulance retrieval teams attending primary missions from 2009-2018. METHODS: Retrospective review of all patients who received blood products with NSW Ambulance retrieval teams between 13/8/2009 and 31/12/2018. RESULTS: A total of 12,468 primary taskings were reviewed, identifying 1,043 (8.4%) cases of prehospital transfusion. The proportion of missions administering blood transfusions doubled between 2009 and 2018. Road traffic incidents were the predominant etiology. Eighty per cent of patients (n = 842) reached hospital alive following transfusion. Retrieval missions had a median time of 117 minutes (IQR 74-168). An initial blood pressure <100mmHg and reduced GCS were strongly associated with prehospital mortality. The median shock index of patients prior to transfusion was 1.2, which reduced to 1.0 after transfusion. CONCLUSION: The use of prehospital blood transfusion for suspected bleeding in NSW Australia has more than doubled since 2010. Patients who received prehospital transfusion arrived at hospital with improved hemodynamic observations.